The present invention relates to a color image recording apparatus in which a color image is formed on a photosensitive pressure sensitive image recording medium upon light irradiation thereto through a mask member on which a mask image is carried in accordance with a color image information.
Copending U.S. patent application Ser. No.184,576 filed on Apr. 21, 1988, and copending British Patent application No. 8809700.1 filed on Apr. 25, 1988 disclose a color image recording apparatus using a mask member. According to the apparatus, each of mask images corresponding to trichromatic resoluted images of an original is formed on each of the mask members as an intermediate recording mediums at a monochromatic printer, and such mask member carrring the mask image is brought into intimate contact with an elongated photosensitive pressure sensitive image recording medium at a given position and is subjected to light exposure at an exposure unit. In this case, the irradiated light has a specific light wavelength corresponding to the resoluted color with which the mask member is recorded with the mask image. Upon the exposure, a color latent image is formed on the recording medium. The photosensitive pressure sensitive recording meidum carrying the latent image is then superposed with a separate developer sheet and these are subjected to pressure-developing at pressure developing unit disposed at downstream of the exposure unit, so that a color output image is formed on the developer sheet.
Incidentally, the image recording medium used is so called a transfer type image recording medium described in U.S. Pat. No. 4,399,209. The image recording medium includes a first image recording medium (the above mentioned photosensitive pressure sensitive recording medium) and a second image recording medium (the above mentioned developer sheet), and the first image recording medium is provided with microcapsules which encapsulate therein a first material having first and second phase dependent on light exposure. The developer medium is provided with second material which provides an output image upon reaction with the first material. The light exposed microcapsules are photo-cured, whereas non-exposed microcapsules are ruptured upon pressure application, so that the first material is flowed out of the microcapsules to react with the second material.
According to this apparatus described in the copending application, when the photosensitive pressure-sensitive sheet is moved at a low speed at the time of the pressure development, a following portion of the photosensitive pressure-sensitive sheet which portion is positioned at the exposure unit is also simultaneously moved, since the photosensitive pressure sensitive sheet is of elongated continuous web-like sheet. Further, in order to prevent the developer-coated surface of the developer sheet from being damaged at the time of feeding the developer sheet toward the pressure developing unit, feed rollers are in rotational surface contact with the back surface of the developer sheet (on which the back surface the developer is not coated) during feeding the developer sheet.
According to the above apparatus, however, as mentioned above, since the photosensitive pressure-sensitive sheet part positioned at the exposure unit is also moved at the time of pressure development, it is impossible to conduct a second exposure to light having a second specific wavelength with respect to the following part of the photosensitive pressure sensitive recording medium with using a second intermediate recording medium (a second mask member on which a second resoluted color mask image is formed). Since the pressure developing operation requires relatively long period, the exposure operation to the following photosenstive sheet part is also suspended by this period, thus reducing the entire speed for color image recordation.
Further, since the feed rollers are arranged to rotationally contact the non-coated surface (back surface) of the developer sheet, it is necessary to flip over the developer sheet so that the developer-coated surface (front surface) of the developer sheet contacts the photosensitive pressure-sensitive sheet. This requires a much elongated sheet feeding path for the developer sheet for its turn-over action and may increase the probability of jamming the developer sheet.